Firewall down? Or just the data collection?

The downtime notification email tells me:

During the previous day, following downtime of your router “Router 1” was recorded:
Firewall: 24 hours
uCollect: 0 hours
The total sum of outages is currently 459 h.

And the Web interface of the Turris says:

Data collection status
uCollect data: Online status updated 7 seconds ago
firewall logs: Online status updated 1781742 seconds ago

Now, first, does it mean the firewall is down, or just the firewall data collection? And, second, how to fix that?

(It may be related to Updater selhal: Failed to fork command /tmp/updater-busybox-jGcFEp/busybox: Out of memory × since it seems it happened around the same time.)